According to the known state of the art, dental malformations (or malocclusions) are corrected by means of the use of orthodontic screws, to bands and brackets that enable the application and locking of orthodontic wires.
Brackets are devices that are attached to the surface of the tooth and used to enable the passage of an orthodontic wire that is laid thereon and fixed with metal and/or elastic bindings or a snap-fastening (self-ligating bracket).
The tensioning of the orthodontic wire (and consequently also of the teeth) is done by attaching bindings between the wire and the brackets, or by inserting the wires inside self-ligating brackets, or by using elastic bands and/or springs, or by activating suitably modeled wires.
Orthodontic screws are inserted in the bone through the soft tissues and the part emerging from the gum or oral mucosa is shaped so as to allow for the anchoring of orthodontic treatment devices, such as elastic bands, springs and orthodontic wires.
The orthodontic screws of known type can therefore allow for the passage of the wire but they do not anchor it in position and a manual action by the operator is consequently always needed to bind the orthodontic wire with a metal and/or elastic ligature to the head of the screw, or to wind the wire around the screw in order to fix it in place, or to apply a bonding substance (e.g. a composite and/or acrylic resins) between the wire and the head of the screw.
Such fixing solutions, involving the winding of the wire or the use of a second (metallic or elastic) binding, or ligature, or the application of other substances, are time-consuming and not very practical, especially when action is being taken in regions that are difficult for the operator to access (e.g. the palate or the molar and premolar areas), and they are sometimes not very safe because they carry the risk of the orthodontic wire slipping from the screw.
In this last case, it would be necessary to take action again, causing considerable discomfort to the patient as well.
According to the current state of the art, moreover, relying exclusively on the teeth as a means of anchorage cannot ensure a stable anchorage for the correction of malocclusions so it has to be reinforced with the aid of extraoral means, such as extraoral traction devices, or the use of elastic bands placed between the arches (intra-oral elastic bands) that always require the cooperation of the patient.
Being attached to the bone, the orthodontic screw enables a stable and to predictable anchorage to be achieved and consequently allows for the correction of malocclusions without needing the patient's cooperation.